Seven years ago this month, Spirit bounced down onto the surface of the Red Planet, rolled to a stop upright, and beeped home, ready to roll. Three weeks later, Opportunity not only bounced down safely and right into a small crater, but opened its "eyes" to see what the Mars Exploration Rovers had been sent to find signs that water had once flowed there.

In the past week there have been 25th anniversaries of two events in 1986, one great, one terrible: the closest approach of Voyager 2 to Uranus on January 24, and the explosion of the space shuttle Challenger upon liftoff on January 28.

I've spent the day noodling around in the current issue of Icarus, following up some of the more interesting stories within its table of contents, and came across a picture of this very cool crater -- actually, set of craters -- on Mars.

Daniel Macháček has reached into the dark side of Prometheus and pulled out an incredible amount of detail where the potato-shaped moon is illuminated by Saturnshine. He produced an animation that morphs among the three sets of four-filter color images that Cassini snapped during the flyby.

A press briefing was held at NASA Headquarters this morning to preview the planned February 14 encounter by Stardust with Tempel 1. There aren't often lots of questions from media after these "preview" briefings, but today there were zero. That's not good.

In the last couple of weeks, media outlets around the world have been reporting that NASA recently convened a private meeting at JPL to identify the worst movies ever made, scientifically speaking. It seemed like a good story. The problem was that it wasn't true.

Earlier this week I got all excited about the Orcus-Vanth system. It turns out there was a math error in the version of the paper that I read, which resulted in the notion that Vanth could be nearly as big as Orcus.

In the past couple of months I've received several emails from scientists offering clarifications, corrections, or alternative points of view to previous posts, which is awesome and something that I enthusiastically encourage. Here's one of them.

A terrific set of Goldstone radar images of a good-sized near-Earth asteroids named 2010 JL33 was posted to the JPL website yesterday. They also posted a movie version but something about these pixelated radar image series absolutely begs for them to be displayed as an old-school animated GIF, so I made one.